Tool for drawing casings from wells.



I. W. DAVIS. TOOL FOR DRAWING CASINOS FROM WELLS.

APPLICATION FILED OCT. 19,-1914.

Patented July 6, 1915.

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UWE/WUR By M En sTaTns PATENT onirica.

AMES W. DAv1s, or coALGATE, OKLAHOMA.

' TOOL FOR DRAWIG CASIN GS FROM WELLS.

Specification of Letters Patent.

Patented July 6, 1915.

. Application led October 19, 1914. Serial No. 867,452.

To all whom t may concern.'

Be it known that I, JAMES W. DAVIS, a citizen of I the United States, residing at Coalgate, in the county of Coal and State of Oklahoma, have invented certain new and useful Improvements in Tools for Drawing Casings from l/Vells, of which the following is a specification, reference being had to the accompanying drawings.

Tools of -this class commonly include a main body portion which is adapted to be attached to a cable or to a drill-stock and let down into the well casing, 'this body being provided with engaging blocks which, when said body portion is pulled upward in the casing, are forced to engage said casing.

.When it is desired to withdraw the tool from the casingl without drawing the latter from the well, it is often diilicult to hold the blocks-away from the inner surface of the casinguntil the tool is withdrawn. u

An object, therefore, of the invention is to provide improved means for overcoming the tion view taken in two lines B-B objection named.

Other objects and advantages of the invention will be set forth in the ensuing description. y Referring to the accompanying drawings, which show one embodiment ofthe invention in 'practical form Figure 1 is an elevation view of the tool. Fig. 2 is an elevathe direction of the arrow A of Fig. v1, but showing some of the parts shifted in position. Fig. 8 is,A Ya sectionalV view taken' on the line-3+?) "of Fig. 1. Fig. 4 is a view in the same direction as Fig. l, showing two engaging blocks. Fig. 5 is an enlarged sectional view taken on the line which'like characters of reference designate likeparts, the improved tool shown includes a cylindrical main body 6, which has a re-- duced screwthreaded upper end 7 for attachment to a'drill-stocl'r. On diametrically opposite sides, this main body portion 6 is cut away to the planes represented by the and B-'B in Fig. 1, thus leaving an upwardly tapering central portion 8; and this central portion is slotted through from one of its plane faces 9 to the other, as at 10. In further arrangement, two engaging blocks 11, shown separated in Fig. et, are provided, and rest against the inclined faces 9 with freedom of vertical sliding-movement, each block having al1/1g 12 which extends into the slot and laps past the lug of its'mate. A pin 13 passes through the central portion 8 parallel with4 the two faces 9 and through slots 14 in the lugs 12 of the blocks 11, thus holding said blocks in assemblage with4 the body 6 with freedom of vertical movement on said faces.

In use, the tool thus described is let down into the casing to be drawn, 'the blocks 11 being' held at end of the tapered "central portion 8 by frictional conta'ct with said casing. Then, by giving the tool a pull upward, the frictional contact of the blocks 11 with the inner surface of the casing draws said blocks downward along the faces 9 toward the lower and larger end of the tapered central portion 8, thus forcing said blocks apart and into lifting engagement with the casing.

The tool thus described is not materially different from one in use at this time.

In further arranging the tool and carrying out the objects stated, all that part of the main body v6 below the slot 10 is bored out axially, and the bore contains a rod 15 having freedom of vertical sliding movement therein except as yieldably limited by improved parts later described. The upper end of this rod 15 is provided with a T head 16; and with a series of ratchet teeth 17, while its lower end is provided with a suitable weight 18. A detent 19 is pivoted in the lower end of the slot 10 by a pin 20 which passes Ithrough the lower portlon of the central tapered portion 8, andthe free end of said detent is adapted to en age successive ones of the ratchet teeth 1 rod 15 as the latter is raised upward. Ordinarily, this detent 19 would engage the teeth 17 by its own gravit action of said detent and in order to have vit prevent the rod 15 from beingtoo sensitive and responding too cidental downward stock, it is provided of the but to insure a quicker just below and fulcruming on a protuberance 24 in the groove and being secured therein by a screw, 25. By adjusting this screw 25, the tension of the spring 22 may be varied to of the detent 119 on the rod 15.

When it is desired to withdraw the tool produce proper resisting action from the casing, the cable or drill-stock to which the tool is attached is given oneor more quick downward thrusts, with the result' that the blocks 11 are, by their own inertia, raised to or toward the uppermost position shown in Fig. 2 out of engagement with thewell casing; and also at each down thrust of the tool the rod 15 is, by its own inertia, raised upward one or more teeth iand caught by the detent 19. In this way,

the tool downward until the lower end of the rod 15 contacts the bottom of the well.

Having thus described the invention, I'

claim In a tool of the class'desoribed, a body, a

. copies of this patent may be obtained for ve cents each, by

portion of said body being tapered upward and having blocks mounted with freedom of vertical sliding movement on said tapered portion, the lower portion of the -b'ody being bored axially and provided with a rod mounted slidably in said bore, said rod hav ing a T head which, with the rod raised upward in said bore, supports said blocks, a detent pivoted in the body at the side of said rod and adapted lto positively hold the latter against downward movement when raised, a spring carried by the body and acting on said vdetent in such manner that the latter yieldably resists upward movement of said rod, and means for adjusting the tension of said spring.

Witness my hand this 10th day of Gotober, 1914.

JAMES W. DAVIS.

Witnesses:

" ROY Wmrnoox,

R. P. CARSON.

addressing the Commissioner of Patents,

Washington, D. C. 

